The invention relates to a mechanism for regulating a wiper motor in a vehicle.
In the traditional wiper regulators, the electrical circuit for the wiper motor is coupled to a wiper switch in series with the ignition switch so that the wipers are automatically turned off when the ignition is turned off. A feature of the commonly used circuit is that when the ignition is turned on again the wipers begin to wipe once again if the wiper switch was not turned off beforehand. This also is the case for wiper regulators with an automatic return to the final position because the wipers are immediately deactivated when the ignition is switched off (normally not in the final position) and when the ignition is switched on again, even when the ON/OFF switch is turned off, it strives to reach its final (resting) position. Very often, the wipers are not turned off but rather are switched into the interval wiping position. This type of interval switch only makes the wipers activate during specified time intervals by means of a time switch so that when the driver turns off the vehicle motor he is not reminded to switch off the wipers even if the wipers are running. If the wiper electrical circuit is only interrupted by turning off the ignition switch, then when the ignition is turned on again the interval circuit is activated again. All these familiar circuits have the idiosyncrasy that the wipers can only be turned on when the ignition switch is turned on, which can lead to destruction of the wiper blades in the case of wipers frozen solid to the window when they are jolted away from the window, or if the windshield wipers do not budge, it can lead to an excessive strain and destruction of the motor or of the wipers themselves. In particular, with a regulator with automatic switching off of the wipers at its end positions, the driver will suffer these consequences if the wipers are coincidentally frozen out of the resting position because the wipers, even upon subsequent turning off with the ON/OFF switch on the dashboard, will strive to reach their resting position when the ignition is switched on.
An object of the present invention is to create a mechanism for regulating a wiper motor in a vehicle, which prevents the wipers from starting up unintentionally when the ignition is turned on. This objection is fulfilled with the circuit having the features of the present invention.